Turnbuckle



July 8, 1969 J. w. HOWLETT TURNBUCKLE orz Sheet Filed May 10. 1965 INVENTOR.

JAMES W. HOWLETT BY W M,

. A TQ NEYS My 9' J. w. HOWLET-r 3,454,293

I TUHNBUCKLE I Filed May 10. 1965 Sheet 3 of 2 FIG. 4

INVENTOR. JAM ES W. HOWLETT ATTORNEYS United States Patent 3,454,293 TURNBUCKLE James W. Howlett, Richmond Annex, Califi, assignor to Howlett Machine Works, a corporation of California Filed May 10, 1965, Ser. No. 454,516 Int. Cl. F16b 7/06; E04g 25/02; E21d 15/14 US. Cl. 28760 3 Claims The invention relates to turnbuckles, and more particularly to a turnbuckle designed to be used as a tension member with wire rope or stranded wire cable.

An extensive use of wire rope or stranded wire cable is in connection with automobile barriers or restraining fences in highway and especially in freeway design. Modern highway and freeway design construction has minimized certain types of traffic accidents but it has been found that a high incidence of fatal accidents is the result of head-0n collisions through penetration by one car of the median dividing strip, or through single car collisions with abutments or other freeway peripheral obstructions following loss of control and consequent violent exit from the travel lane by the automobile. As an effective means of containing automobiles within the freeway lanes, median-strip barriers and berm barriers have been utilized. Such barriers comprise generally a chain-link metal fabric supported on posts and utilizing one or more strands of Wire cable supported horizontally above the ground level by clips on the posts. In such applications the wire cable is provided in approximately 500 foot lengths, connected with appropriate turnbuckles for joining and tensioning an extensive run of cable which may extend without anchorages to the ground for up to one mile or more.

In such a composite wire cable-chain link barrier, the cables must function as the major restraining element in preventing the colliding automobiles from penetrating the barrier into the adjoining lane of traffic or into the abutment or other obstacle the barrier is intended to protect from. In the type of barrier described each of the elements must cooperate to achieve the designed goals which are to restrain and prevent penetration of the barrier; to effect gradual deceleration of the impinging vehicle; and to retain the vehicle if possible in contact with the barrier so as to prevent or limit a rebound or ricochet of the vehicle from the barrier into uncontrolled contact with other traffic.

It is anticipated that the chain link fabric will tear and will tangle about and entwine with the colliding vehicle, which in its forward motion will both carry along the entwined link fabric but also successive posts which are, depending upon the force of the collision, broken, or bent and pulled from their attachment with the surface or subsurface mounting. The entire colliding mass including vehicle, mesh fabric and posts will thus ride along the wire cables, and the primary deceleration resistance is provided by the friction brake effect of the cable clamps which secure the cable to the posts being carried along the cable. It will be apparent therefore that the design of the tumbuckle is of paramount importance since it is subjected both to substantial shock loads upon impingement of a colliding vehicle with the barrier, is itself exposed to impact with the vehicle, and must by its configuration and design offer as little impediment as possible to the sliding of the wire cable clamps and attached poles, link fabric and vehicle along the cable to prevent a suddent pileup of the clamps which would tend to result in the inertial en ergy of the trapped vehicle tearing it free of the barrier and into uncontrolled movement.

It is therefore an object of the present invention to provide a turnbuckle for wire rope or cable which shall be of a minimum greater diameter or cross section than the cable it is designed to be attached to and co-function with.

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Another object of the invention is to provide a turnbuckle which may be utilized under conditions of exposure to impact with the possibility of damage to the turnbuckle minimized and restricted to easily replaceable parts.

A further object of the invention is to provide a turnbuckle design utilizing few parts, which are adapted to ready assembly and disassembly under service conditions.

A still further object of the invention is to provide in a turnbuckle means of accommodating substantial variations in the length of wire rope or cables connected thereto.

Another object of the invention is to provide a turnbuckle formed of a number of substantially simple parts, which parts may be selected materials having different physical characteristics to effect specific desired performances of the turnbuckle, and enabling maximum economy in manufacture. Still other objects, features and advantages of the present invention, other than those expressly set forth hereinbefore, are inherent in or implied from the novel combination, construction, and arrangement of the parts and components in a manner to produce the many useful results to which the invention is directed in whole or in part.

In the accompanying drawings wherein the same reference characters have been employed to designate the same or similar parts throughout the several views thereof;

FIGURE 1 is a side view of a turnbuckle constructed in accordance with the preferred embodiment of the present inventions;

FIGURE 2 is a side view in perspective of an installation in a typical application of the turnbuckle the subject of the present invention;

FIGURE 3 is a longitudinal cross sectional view of the invention shown in FIGURE 1 taken along the line 3-3 of FIGURE 1;

FIGURE 4 is a longitudinal cross sectional view taken along the line 4-4 of FIGURE 1;

FIGURE 5 is a longitudinal cross sectional view taken along the line 55 of FIGURE 3.

The invention generally, and shown in FIGURE 1, comprises a turnbuckle 9 having a generally cylindrical tubular body or housing 11 carrying in connectable engagement therewith at opposite ends thereof cable anchoring pieces 12 and 13 respectively, said cable anchoring pieces and as shown, being of substantially the same outer diameter as the body 11 and defining therewith in attached position substantially a longitudinal extension thereof of similar transverse extent. Tubular body 11 has preferably, and as shown in FIGURES 3 and 4, substantially imperforate side walls 14 defining a central bore 16. Body member 11 carries at the outer ends thereof adjacent cable pieces 12 and 13 reduced internal bore portions 17.

The bore portions 17 are internally threaded with threads of opposite hand whereby when suitable screws are threadably engaged in the opposite ends of the body 11 one revolution of the body will cause the screws to move simultaneously one thread lead; thus if the body member is rotated one revolution in one direction screws will be caused to move toward each other by the distance of two thread leads and upon reversal of rotation of the body the screws will move apart the distance of two thread leads.

As shown in FIGURE 3 the reduced bore 17 adjacent cable end piece 12 only is shown, it being clearly understood that a similar but reversed thread construction is provided in the body 11 adjacent the opposite cable end piece 13. The bore 17 is as shown provided with internal threads 18 adapted for receiving in threadable engagement therein a screw end piece 19, one of a pair of screws 19 and 20 respectively, as shown in FIGURE 4, engaged at opposite ends of the body 11, and each of said screw end pieces being provided with opposite hand threads.

It is a feature of the present invention to provide readily replaceable screws in which, normally, unavoidable damage is desirably concentrated when the turnbuckle assembly is subjected to sufficient force upon collision by an automobile, and accordingly and as shown in FIGURE 3 the end piece 19 is arranged to serve as an operative connection between the cable anchor 12 and the body 11 of the turnbuckle. The cable anchoring piece 12 is formed with a cylindrical wall 21 having an outer diameter substantially coterminous with that of the body 11, as shown in FIGURE 1. Internal bore 22 of the anchor 12 is provided with an internally threaded portion 23 arranged for threadable engagement with the outer end of screw 19, and as shown in FIGURE 3, whereby cable anchor 12 may be threaded upon the said outer end 24 of screw 19.

As one means of retaining the cable anchor piece and its associated screw in fixed, threaded engagement and as here shown the screw 19 is provided with a transverse slot 26 adapted for registration with aligned holes 27 and 28 provided in the cylindrical wall 21 of the cable anchor 12. It will be apparent from the foregoing, and with reference to FIGURES 3 and 5, that cable anchor piece 12 may be threaded upon screw 19 sufficiently as to bring the slot 26 in the end 24 of the screw into registration with the aligned bores 27 and 28 of the anchor piece, permitting pinning of the cable anchor and the screw by means of split pin 29, shown in disassembled relationship in FIGURE 3 and in assembled position in FIGURE 5. Bores 27 and 28 are provided with chamfered portions 31 and 32 adjacent the exterior ends thereof to aid in ready insertion of the pin 29 which is likewise provided with tapered ends 33 and 34 to assist in easy entry and removal. Assembly and disassembly of the cable anchoring piece to and from its associated screw is thus afforded, together with a means for positively locking the anchor and engaged screw against relative rotation.

It is common procedure to shop assemble the cable anchoring pieces 12 and 13 to their respective steel cables by means of swaging and in FIGURE 3 cable anchor 12 is shown afiixed to the cable after the swaging operation. The anchor piece internal bore 22 has as the result of the swaging operation been reduced in internal diameter over the portion 36 in contact with wire cable 37, and the side wall 21 of the anchor piece has been correspondingly elongated and reduced in wall thickness in the area 38 overlying cable 37. The method of attachment of the anchor piece 12 to the screw 19 by means of the internal threaded bore affords protection to the threaded portion of the anchor piece in case of a colliding automobile, with the result that the anchor pieces 12 and 13, as shown in FIGURE 2 aflixed to wire cables 37 and 39 respectively, are generally preserved from damage, eliminating the necessity of field replacement of the anchor end pieces of the cables.

It will be apparent that the requirement of malleability in the cable anchoring pieces .12 and 13 to enable the swaging operation would make it generally infeasible to form the screws 19 and 20 integral with the anchoring pieces; the present invention affords the opportunity of utilizing materials of different physical characteristics in the separate parts, permitting inexpensive heat treatment of the screws, for example, to develop their desired characteristics which differ markedly from those of the cable anchoring pieces.

As shown in FIGURE 2, the turnbuckle 9 is assembled as part of a continuous tension member comprising threadably attached cable anchor end pieces 12 and 13, and their respective wire cables 37 and 39. The wire cables are positioned on a plurality of posts defining the midline of the highway barrier, and as here shown such posts comprise a series of H channels 41 positioned in substantially perpendicular, parallel spaces relationship. The method of positioning the cables on the supports 41 as shown comprises U clamps 42 including a U-shaped bracket having threaded end portions engaged through a substantially flat base strap 46 and retained by nuts 47. The completed barrier includes a chain link or wire mesh unless the U-bolts 42 still attached to uptorn supports 41 either underlying or overlying the cables and turnbuckle assembly.

Impact of an automobile with the highway barrier generally involves a low-angle collision rather than rightangle or head-on to the barrier positioning; the barrier is thus subjected to substantial shear forces with distortion and tearing of the wire mesh fabric and bending, deformation and breaking of the supports adjacent their anchorage in the ground. The wire cable-turnbuckle assembly often is the only continuous element in the barrier and as such the full remaining force of the collision following initial impact must be resisted by it. A number of supporting posts together with torn wire mesh fabric may be carried by the colliding automobile along the wire cable-turnbuckle structure and it will be apparent that unless the U bolts 42 still attached to uptorn supports 41 can slide over the turnbuckle assembly with as little impeding as possible the entire mass of automobile, posts and wire mesh fabric will be brought to a sudden halt by impingement upon the turnbuckle, with consequent damage to the automobile and its occupants.

FIGURE 1 shows the turnbuckle assembly joining the ends of wire cables 37 and 39 with the screws 19 and 20 threadably engaged between opposite ends of the turnbuckle body 11 and cable anchoring end fittings 12 and 13 respectively and entirely concealed within the internal bores of the anchor pieces and the body. FIGURE 1 makes clear also the tapered relationship of the turnbuckle relative to the wire cable, whereby the swaged portion of the cable anchoring end pieces 12 and 13 serve as a desirable taper from the smaller diameter of the wire cable to the maximum diameter established by the cable end pieces and the substantially coterminous exterior diameter of the turnbuckle body 11. Thus upon impact from either end of the turnbuckle minimum resistance is presented to supporting clips sliding along the wire cable deriving maximum deceleration effect and avoiding a sudden stoppage of forward movement of the clamps being carried by the colliding automobile.

Latitude in adjustment of the tension in the wire cables 37 and 39 is afforded by the provision in the screws 19 and 20, respectively, of sufficient length as to afford any desired variation between maximum and minimum turnbuckle extant.

As will be noted from the description of the installation, and with reference to FIGURES 3 and 4, the exterior surfaces of the turnbuckle assembly are resistant to impact and the threaded portions of the cable end pieces 12 and 13 and the turnbuckle body 11 are entirely internal, and hence protected from injury. Where the turnbuckle in its tightened position entirely encloses the screws 19 and 20, as shown in FIGURE 1, the screws are likewise protected from impact injury, but in many installations the fully engaged position of the turnbuckle and the associated cable end pieces will not be obtained, and a portion of screws 19 and 20 will be exposed between the separated cable anchoring end pieces and the ends of the turnbuckle body 11. In accordance with the invention, it is contemplated that it may be desirable to localize damage, if any, to the turnbuckle assembly to the easily replaceable screws 19 and 20, and they consequently may be formed of a material having a lower yield point than the material forming the turnbuckle body 11 or the cable anchoring end pieces 12 and 13, whereby upon impact the screws may suffer elongation and bending deformation and through their sacrifice minimizing stress to and preventing damage to the other parts of the turnbuckle. It will be obvious that screw end pieces 19 and 20 are identical but of opposite hand threads, and lend themselves to convenient and easy field replacement Where necessary.

If desired, the body 11 of the turnbuckle may be formed in two pieces, and as shown in FIGURE 4 such two pieces comprise portions 49 and 51 each having an internal threaded portion 52 and 53 respectively, portions 52 and 53 being threaded to receive a cylindrical connector 54 provided with external thread 56 engaging in the threaded portions 52 and 53 to thereby align and join sections 49 and 51 of the turnbuckle body 11. As shown in FIGURE 4a means is provided for locking the portions 49 and 51 against relative rotation and unintended disassembly, and such means comprises a counter bore 57 on the midline of the threadably engaged portions 49 and-51 of the turnbuckle body 11, said counter bore 57 adapted to receive a split pin 58 which, when seated in the counter bore 57, locks the portions 49 and 51 against relative rotation. If desired, portions 49 and 51 comprising the body member 11 of the turnbuckle may be provided with annular enlarged shoulders 59 and 61 respectively, and which shoulders may be formed with a plurality of transversely extending shallow indentations 62 or other serrations for improved gripping by a suitable wrench for tightening or loosening of the turnbuckle. It should be noted that the turnbuckle body 11 together with cable anchoring end pieces 12 and 13, when the pins 29 are assembled, presents a substantially imperforate outer surface thus affording maximum protection to the interior bores of the turnbuckle parts and to the screws 19 and 20 threaded therein, such protection against weathering, deterioration and damage increasing the serviceability and ready adjustment of the turnbuckle.

I claim:

1. A turnbuckle comprising:

an elongated housing of substantial length formed by two tubular housing halves, said halves each being formed at a first end thereof with oppositely handed internally threaded portions extending inwardly of said ends a minor distance relative to the length of each half and formed with internal bores of greater diameter than said threaded portions extending from said threaded portions to second ends of said halves,

means for detachably securing said halves together at said second ends for unitary rotation of said housing,

a right hand externally threaded end piece threadably engaged in one of said internally threaded portions and a left hand externally threaded end piece threadably engaged in the other internally threaded portion, each of said end pieces being formed and dimensioned to extend outwardly of the housing when threadably engaged therein,

a pair of tubular cable anchoring means each formed and dimensioned for receiving and securing in one end thereof a wire rope or stranded cable and each formed at its opposite end with an internally threaded bore threadably engaging the outwardly extending ends of said end pieces.

2. A turnbuckle as defined in claim 1 wherein said anchoring means is formed of a malleable material suitable for swaging onto said cable for securing said cable thereto, and means for releasably locking said end pieces against rotation relative to said anchoring means.

3. A turnbuckle as defined in claim 2 wherein said end pieces are formed of a constant diameter for threadable engagement in said housing and anchoring means and are heat treated for sufiicient strength to have a yield point which is slightly less than the yield point of said malleable anchoring means and said housing.

References Cited UNITED STATES PATENTS 932,744 8/ 1909 Adams.

973,008 10/1910 Cyr 254-54 1,068,144 7/ 1913 Lawler 287-61 X 2,354,474 7/ 1944 Noble et al 287- 2,479,096 8/ 1949 Bratz 287-60 2,479,172 8/1949 Landon 287-60 2,678,225 5/1954 Wright 287-60 3,065,007 11/ 1962 Colmer 287-60 3,081,116 3/1963 Weiner et a1 287-60 CARL W. TOMLIN, Primary Examiner.

A. V. KUNDRAT, Assistant Examiner. 

1. A TURNBUCKLE COMPRISING: AN ELONGATED HOUSING OF SUBSTANTIAL LENGTH FORMED BY TWO TUBULAR HOUSING HALVES, SAID HALVES EACH BEING FORMED AT A FIRST END THEREOF WITH OPPOSITELY HANDED INTERNALLY THREADED PORTIONS EXTENDING INWARDLY OF SAID ENDS A MINOR DISTANCE RELATIVE TO THE LENGTH OF EACH HALF AND FORMED WITH INTERNAL BORES OF GREATER DIAMETER THAN SAID THREADED PORTIONS EXTENDING FROM SAID THREADED PORTION TO SECOND ENDS OF SAID HALVES, MEANS FOR DETACHABLY SECURING SAID HALVES TOGETHER AT SAID SECOND ENDS FOR UNITARY ROTATION OF SAID HOUSING, A RIGHT HAND EXTERNALLY THREADED END PIECE THREADABLY ENGAGED IN ONE OF SAID INTERNALLY THREADED PORTIONS AND A LEFT HAND EXTERNALLY THREADED END PIECE THREADABLY ENGAGED IN THE OTHER INTERNALLY THREADED PORTION, EACH OF SAID END PIECES BEING FORMED AND DIMENSIONED TO EXTEND OUTWARDLY OF THE HOUSING WHEN THREADEBLY ENGAGED THEREIN, A PAIR OF TUBULAR CABLE ANCHORING MEANS EACH FORMED AND DIMENSIONED FOR RECEIVING AND SECURING IN ONE END THEREOF A WIRE ROPE OR STRANDED CABLE AND EACH FORMED AT ITS OPPOSITE END WITH AN INTERNALLY THREADED BORE THREADABLY ENGAGING THE OUTWARDLY EXTENDING ENDS OF SAID END PIECES. 